Glass used as walls
Glass used as walls
(OP)
since most clients choose glass walls to be installed for residential house, what are the remedies (structural design) to resist lateral forces?
When was the last time you drove down the highway without seeing a commercial truck hauling goods?
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RE: Glass used as walls
RE: Glass used as walls
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Glass used as walls
RE: Glass used as walls
Maine EIT, Civil/Structural.
RE: Glass used as walls
The 2x4's, silly.
RE: Glass used as walls
Maine EIT, Civil/Structural.
RE: Glass used as walls
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Glass used as walls
Glass: Very impressive... Is this a non-EQ zone? Otherwise how did you address post-EQ reliability?
RE: Glass used as walls
- glass is infinitely strong in compression
- structural silicone between panels makes the panels work together in plane as a pretty effective shear wall
- there was another concrete shear wall out of the shot.
- project was in Santa FE, NM
- it was laminated glass and had other layers of redundancy built into the concept.
See attached for another glass wall building, actually with a glass beams and a glass roof also. We completed in Times Square NYC in 2008.
RE: Glass used as walls
I firmly believe that structural reliability methods properly applied to brittle materials can produce structures with the same level of safety that can be had in ductile construction. It takes more skill but, then, we've got the technology.
Post-Christchurch, some are even starting to question if ductility is really even all that great. Preventing collapse is nifty but having to demo half your building stock is not. This manner of thinking is consistent with performance based design principles. Any material can be put to work so long as its limitations are respected.
I'm currently reading a book called "the stone skeleton". It's about the structural design of brittle,unreinforced, mortarless masonry and stone. Safety factors are based on geometry in that world rather than stress or ductility. There are cathedrals built using these principles that have survived major earthquakes, heavy WWII bombing, and foundation settlements that would get a modern building condemned.
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Glass used as walls
I'm really not sure I'd ever want to have at something like that.
RE: Glass used as walls
We are talking about a material that sort of spontaneously explodes for no reason after all. Nobody's pitching high rise elevator shafts in glass just yet. Although I'm sure there's some maniac at Delft looking into it for after CLT skyscrapers get boring.
Other than the odd guardrail, I leave glass design to the experts. As a material, it's not nearly forgiving enough to accommodate the fumblings if a uninitiated hack.
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Glass used as walls
The interesting thing about the tempered glass in the code is the apppication / new requirement for heat-soaked tempered if you are not wanting to use other laminates. Heat soaking encourages those panels with inclusion(s) to fail. They don't always fail during the heating and cooling, but the inclusions tend to have grown and this makes the panel even more likely to fail catastrophically.
RE: Glass used as walls
BA
RE: Glass used as walls
Maine EIT, Civil/Structural.
RE: Glass used as walls
http://www.dailymail.co.uk/news/article-2204095/St...
RE: Glass used as walls
BA
RE: Glass used as walls
RE: Glass used as walls
There was an article in a recent Modern Steel Construction where they talked about connecting the glass pieces together to act as a shearwall at some new buildings at Colorado School of Mines, but it had a steel gravity load system.
Glass's 1st pic is cool, but I would be scared with snow and window buckling the skinny brittle glass wall. But then that is why I don't design in glass.
RE: Glass used as walls
What I'm thinking is that the system would be required to meet ULS requirements in absence of all glass, possibly at a reduced load combination like 1.2D + 1.0L.
Using it for seismic only and having a full gravity system would seem reasonable, so long as we are talking about VERY robust glass systems.
Glass99: What type of glass panes would you be recommending for this kind of work? It makes me think of the polycarbonates I used in antiterrorism work. Lay up tempered on two faces with polycarb perhaps?
RE: Glass used as walls
In terms of impact, its not that hard to break the outer ply, but breaking subsequent plies takes a really substantial whack. Its more in the scale of multiple sledgehammer blows.
Nickel sulfide is not the thing it used to be. The float lines have really cleaned up their acts in respect to sulfur content. Also heat soak testing goes a long way. CELinOttawa: Cardinal had a widely cited study which spooked a bunch of folks about heat soaking in the US. People are getting over that now, primarily because heat soaked glass rarely gets NiS breakages. Its not 1995 any more!
KootK - yes I know John Kooymans from conferences mostly.
RE: Glass used as walls
RE: Glass used as walls
I think your analogy is a poor one. Unreinf masonry/stone often relies on its own weight and a thick cross section to keep stresses low. In that 1st pic it looked like the glass was the gravity load system as well. P-delta under some combinations and low out of plane buckling strength were my concerns. Clearly it can be done though.
RE: Glass used as walls
RE: Glass used as walls
The part of glass design that really unmans me is discrete bolted connections. I think that connections is where the lack of ductility is the most dangerous. FEM on a bolt hole with the requirement to "know" maximum stresses is a scary prospect.
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Glass used as walls
-> I like to tell clients - Glass is a fickle mistress. She wants the soft touch of the Spanish lover, not the rough hand of the Russian sailor.
RE: Glass used as walls
I don't really do any work in glass but I am infinitely curious about using glass as a structural element and its design. What approach or design guide/manual do you typically follow? It seems like every design needs extensive FEA and testing outside of typical store front or curtain wall design. Do you work for a glass contractor or do you specialize in glass design, if you don't mind me asking. I'm just curious who does these type of designs.
I've read the book "Structural Use of Glass" by Matthias Haldimann which suggests a new approach to designing glass I think it was called the lifetime prediction model. I'm curious if that is used in practice?
Thanks!
EIT
www.HowToEngineer.com
RE: Glass used as walls
RE: Glass used as walls
Not to start a readit/ama but....
How did you get into glass design?
EIT
www.HowToEngineer.com
RE: Glass used as walls
RE: Glass used as walls
EIT
www.HowToEngineer.com
RE: Glass used as walls
RE: Glass used as walls
RE: Glass used as walls
IStructE Structural Use of Glass In Buildings
RE: Glass used as walls
In regards to point glazing being very particular. Do recieve design properties to use in your FEM model from the point support manufacturers or is there somewhat of a standard? Is there much testing involved when you design these glass supported structures to verify these FEM models? I imagine there being many FEM models for just about each different piece of glass, do you guys have some sort of library of glass units that you modify? Sorry, all very fascinating to me. My father-in-law actually owns a small glass company, I've had distant dreams of constructing a glass bridge.
EIT
www.HowToEngineer.com
RE: Glass used as walls
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Glass used as walls
Can you give us some shear values on that silicon product that you are stating makes your panels act like a shear wall? Pretty incredible photo by the way. Every architects dream. Also, I have never seen an infinitely strong allowable compressive stress in a material, except on my home planet of Krypton. Do you have some glass charts we could see with the allowable stress set to "infinity".
RE: Glass used as walls
On a fibre by fibre basis, glass is stronger than most steel. It's only imperfection induced fracture mechanics stuff that reduces the strength drastically in tension.
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Glass used as walls
There is technically a compressive strength of glass, but it is close enough to infinity. Its of the order of 1000ksi. Failure in compression structures is always a function of secondary tension stresses like poisson's ratio effects or buckling.
RE: Glass used as walls
RE: Glass used as walls
RE: Glass used as walls
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.